28 



STUDIES IN IMMUNITY. 



against iV of a 24-hour culture, a fatal dose, and even against T V of a 

 culture. 



A few days later an edema was produced in this rabbit by con- 

 stricting the root of the ear with a rubber ring (edema fluid U A"). 



One of the fore legs received the same treatment, and, on tapping, 

 a clear liquid, edema fluid "B," was obtained, which was slightly 

 pinkish but contained very few leucocytes (one to two hundred per 

 cubic mm.). A few cubic centimeters of blood were then taken and 

 found to contain 3600 leucocytes. The serum of a normal rabbit 

 was used as a control. One cubic centimeter of each of these fluids 

 was put in a separate tube. A platinum loop from a 24-hour 

 culture of the organism suspended in 5 c.c. of salt solution was 

 placed in each tube. 



EXPERIMENT WITH EDEMA "A" (FROM EAR). 



EXPERIMENT WITH EDEMA "B" (FROM LEG). 



The day following inoculation the tubes containing normal rabbit 

 serum and edema fluid were both cloudy and filled with vibrios; 

 the serum of the vaccinated rabbit was perfectly clear. Two days 

 later a culture made on agar from this serum showed that it had 

 remained sterile. The difference in bactericidal power between 

 the edema and the serum of the vaccinated animal is therefore 

 evident. 



